Transmission gearing



Oct. 22. 1940. w CQTTERMAN 2,218,813

TRANSBISSION GEA'RING Filed Aug. 28, 1939 2 Sheets-Sheet l Oct. 22. 19 I F w. COTTERMAN TRANSIISSIONY emnme Filed Aug. 28, 1939 1 2 Sheets-Sheet '2 INVEN 70/? Patented Oct. 22, 1940 UNITED STATES PATENT OFFICE TRANSMISSION GEABING Frederick W. Cotterman, Dayton. Ohio, alllgnor of one-half to Bessie D. Apple, Dayton, Ohio Application August 28, 1939, Serial No. 292,219

25 Claims. (01. It-280) This invention relates to power transmitting devices and is particularly applicable to automotive use. The principle involved is in many respects similar to that of the transmission gear 5 used in my copending application Serial No.

180,174, filed Dec. 16, 1937, except that in the copending application free wheeling is prevented in all speed ratios while in the present application it is prevented only in the overdrive ratio.

10 The present device, like that shown in the copending application mentioned is intended preferably to be used in series with a speed-torque controlled unit and with a separate reversing gear set, such for instance as the hydraulic unit 16 and the reversing gear box in the copending application. v

An object of the invention is to provide a simple and emcient arrangement wherein a single three element planetary gear set comprising a reaction I) gear, a carrier and its pinions, and a coaxial gear may be automatically connected variously at predetermined speeds to the input or output members to provide an underdrive, a direct drive, and an overdrive ratio.

I .5 Another object is to so construct and arrange and to so connect the several elements of the three element planetary gear set that at rest or at a relatively low speed it is connected to provide an underdrive, but, at a higher speed-by 3 automatically making a single additional connection between two of the parts, without unmaking any connection already made, a direct drive ratio will result, and, at a still higher speed, by automatically making another single additionll a1 connection between two other of the parts,

- without unmaking any connection already made,

an overdrive ratio will result.

Other objects and advantages will be seen as the invention is described in detail and reference is made to the drawings, wherein,

Fig. 1 shows the gear set with a centrifugal device on the output member for changing from underdrive to direct drive, and a second centrifugal device on the carrier element for changing from direct to overdrive.

Fig. 2 shows the gear set with a centrifugal device on the ring gear element for changing from underdrive to direct and a second centrifugal device on the input member for changing from direct to overdrive.

Referring particularly to Fig. 1, a housing I0 is closed at the rear end but has a separate cover l2 held on by screws, not shown, for closing the I front end. Cover l2 has a hub It provided with a bearing bushing it within which the front end of the input shaft I8 is runningly fitted.

The hub 20 of the sun gear 22 is end splined at 24 to the hub ll; whereby the sun gear is at all times held non-rotative. A bearing bushing 45 26 is press fitted into the sun gear 22 and runningly fitted to the shaft II.

The output member comprises the output drum 28 which is provided at the rear end with the output shaft 30 rotatably supported in housing ID by the ball bearing 32, and at the front end with a cover 34 held to the member 28 by screws 36. The cover has a hub '98 which has press fitted therein abearing bushing 49, the bushing 40 being runningly fitted overv the hub II. A 5 thrust washer l2 separates the covers l2 and 34.

A centrifugal weight housing 44 is end splined at 48 to the hub 3|. Housing 44 is radially bored to slidably receive a weight 50 operable radially outward by centrifugal force at a predetermined speed against the resistance of a spring 52. The inner member 46 of a one way roller clutch 54 is an integral part of the housing 44. A bearing bushing 56 extends through both the housing 44 and clutch member it, being press fitted therein and runningly fitted to the outside of the hub 20 of the sun gear 22.

Since the output shaft II, drum 2', cover 34, hub 38, weight housing 44, weight 50, and inner clutch member 46 are all secured together for 80 unitary rotation, these parts, as assembled in Fig.

1, may be referred to as the output member of that structure.

The planet pinion carrier comprises a carrier front flange 69 having a bearing bushing 62 press fitted therein, the bushing 62 being runningly fitted over the outside of the sun gear hub 20. The outer member 64 of the roller clutch 54 is made an integral part of the carrier flange 69.

I The carrier rear flange 5 has integraltherewith a weight housing it which is radially bored to slidably. receive a weight 68 operable radially outward by centrifugal force at predetermined speed against the resistance of a spring III. A bearing bushing 12 is press fitted into the flange 4.5 65 and housing 66 and runningly fitted over the shaft ll.

Hubs "extend toward each other from the carrier flanges SI, and 65, their ends being held together by the bolts 16 thereby forming a journal upon which the planet pinions 18 are rotatable, the pinions having press fitted therein the hearing bushings II which are rotatable on the journals.

Since the parts consisting of the flanges 60 and 2 me rs This ratio i's-directdrive, the outputand input 88, member 84, housing", weight 88, hubs I4, bolts I8, and pinions I8 areall joined together for unitary-rotation, these parts, when assembled asinPlg.1,maybereferredtoasthecarrier 5 element of that structure.

.. the ring gear element comprises the ring 8.

84, a front bearing head 88, and a rear bearing head-=88, all held together in concentric relation bythe bolts 88 and nuts 82. The heads both.

shaftsrotatlng at'the-samespeed.

qAtabout 35 H. or such other speed for which the weight 88 and spring I8 are designed,

the weight it moves out and tries to enter the opening I28 which. nowlis rotating about 80% faster than the Byagain'decelerating 'the engine until-the opening-I28 drops 3096 in speed while the vehicle keeps weight speed (aqqihave'ehpenings 84 :to clear thee-nuts: 82 the 28:1

i frontheadfli'carries -thew rini ll withwopenings. 8 -38 =outer=end fofthe "weight". Abearingbushingfl-prwsfittedinto fronthead rotatabiy'supports 'the frontfhead on 'the' hub 88, while another bearing bushing 188 press fitted into the rear head 88 rotatably supports the rear head on the shaft I8.

Thrust washers I82 and I84 limit the movement of the heads88 and 88 respectively. The outer member I 88 of a roller'clutch I88 is made as an integral part of the rear ring gear bearing" head 88. 7 Since the ring gear 84, heads 88 and 88, bolts 88, and outer clutch member I88 are all joined as for unitary rotation, these parts, when assembled as in Fig. '1, may be referred to as the ring gear element of that structure.

An input member flange II2 has intemal' splines to fit over the external splines I I4 on the input shaft I8. The inside of the output shaft 88 has press fitted therein a bearing bushing I I8, the rear end of the input-shaft I8 being rotatable in this bushing.

A rim II8 having an opening I28 to receive the outer end 'of the weight 88 is intergal with the flange H2. The inner member I22 of a one way roller clutch I88 is formed as-an integral part of the input member flange I I2.

- Since the input shaft I8, inner clutch meniber 40 I22, and input member flange I I2 are secured together for unitary rotation, these parts, when assembled as in Fig. 1, may be referred to as the input member of that structure.

. The roller clutch 84 is so formed that, through it, the carrier element may drive the output member forwardly but not backiwardly, the roller clutch I88 being so formed that, through it, the input member may drive the ring gear forwardly but not backwardly. By forward rotation is meant clockwise when viewed from the left of the The device Fig. 1 operates as follows:

When power at low speed is applied to the input shaft I8, the drive will be through clutch I 88 to the ring gear element, to the carrier element,

through clutch 84 to the output member.

Free wheeling being permitted through either clutch, there will now be no engine braking. This ratio is underdrive, the output shaft rotating at so about .7 of the input.

At 15 M. P. E, or any other predetermined speed for which the weight and spring are designed, the weight 88 moves out and tries to enter the opening 88. The opening is now rotating 88 about 30% faster than the weight. By decelerating the engine, the opening drops in speed while the vehicle momentum keeps the weight from falling. When the opening 88 drops in rotative speed to that of the weight 88, the weight 70 enters the opening. The drive isnow from shaft I8, through clutch I88, to'th'e gins gear element, then through the 'weight 88 to the output member. The carrier now idles, transmitting no power. Free wheeling being still permitted 78 through clutch I88, there'is no engine braking.

:is' now the I I8 H2 .and weight 18 to --.-the-weight -88 to output member. --overdrive ratio; wherein the input shaft 'rotates' only .7, as fast as the output member. Both; clutches, and I88 are now'overrunning, but

sincetheinmtmeinberisdirectlyoonnectedto the carrier element by the weight 88 and the ring gear element is tot-he output member by' the weight 88; there is no free wheeling, and consequently there is engine braking as long as overdrive ratio is in eifect.

Referring-particularly to Fig.2, .a-housing I8 the input shaft I8 is runninglyfltted.

The hub 28 of the sun gear 22 is end splined at' E 24 to hub I4, whereby the sun gear is at all times held nonrotative. A bearing bushing 281s press fitted into the sun gear 22 and runningly'fitted over the shaft I8.

The output member comprises the output I 21 which is provided at the rear end with the output shaft 88 rotatably supported in the housing I 8 by the Imll bearing 82, and at the front end with a cover 88 held to the member 21 by the screws 88. The cover 88 has a short hub 88 which has press fitted therein a bearing bushing 4|, the bushing 4i being runningly fitted over the hub I4. The outer member 81 of a one way roller clutch 84 is an integral part of the head 88. A thrust washer 42 separates the covers .I2 and 88.

Since the output shaft 88, drum 21, cover 88, and clutch member-81 are all joined together for unitary rotation, these parts, when assembled as in Fig. 2, may be referred to as the output member of that structure.

The planet pinion carrier comprises the carrier front flange 88 having a hub 88 which has a hearing bushing 8i press fitted therein, the bushing being runningly fitted over the hub 28 of the sun gear 22 and the hub I4 of the bearing head. The forward end of the hub 88 has external splines 88 to which the internal splines of the inner member 41 of the roller clutch 84. are snugly fitted.

The carrier rear flange 88 is provided interiorly with a bearing bushing I8 rotatable on the shaft I 8. .Hubs I4 extend toward each other from the carrier flanges 88 and 88, their ends being held together by the bolts I8, thereby forming a journal upon which the planet pinions I8 are rotatable, the pinions having press fitted therein the bearing bushings 88 which are rotatable on the Journals.

Since the parts consisting of the inner roller clutch member 41, hub 88, flanges 88 and 88, hubs I4, bolts I8, and pinions I8 are all connected together for unitary rotation, these parts, when ,assembled as, in Fig. 2, may be referred to as the carrier element of that structure.

'Ihe ring gear element comprises the ring gear Iii) careers 84, a front bearing head 82, and a rear bearing head 8|, all held together in concentric relation by the bolts 80 and nuts 82. Die heads both have openings 84 to clear the nuts 82.

Formed integral with the front head 82 is the centrifugal weight housing 88 radially bored to slidably receive a weight 88 operable radially outward by centrifugal force at, a predetermined speed against the resistance of a spring 82.

A hearing bushing 83 is press fitted into the housing 43 and runningly fitted over the hub 58 of the carrier flange 88. The output member drum 21 carries the rim 88 with openings 88 into which the weight 50 may enter when it moves outward under the influence of centrifugal force.

Formed integral with the rear head 8| is the inner member I23 of a one way roller clutch I08. A bearing bushing I0| is press fitted to the inside of the head 8| and runningly fitted over the shaft I8. A thrust washer I08 separates the head 8| and the output member drum 21.

Since the ring gear 88, heads 82 and 8|, bolts 90, centrifugal weight housing 88, weight 80, and inner roller clutch member I23 are all connected for unitary rotation, these parts, when assembled as in Fig. 2, may be referred to as the ring gear element of that structure.

A centrifugal weight housing 81 is internally splined to fit snugly over the external splines I ll of the input shaft I8. Housing 81 is radially bored to slidably receive a weight 88 operable radially outward by centrifugal force against the resistance of a spring I0. The outer member I08 of a roller clutch I08 is an integral part of the housing 61.

Since the input shaft I8, weight housing 81, I

and outer roller clutch member I08 are joined for unitary rotation, these parts, when assembled as in Fig. 2, may be referred to as the input member of that structure.

The roller clutch 58 is so formedthat, through it, the carrier element may drive the output member forwardly, but not backwardly, while the roller clutch I08 is so formed that through it, the input member may drive the ring gear forwardly but not backwardly. By forward rotation is meant clockwise when viewed from the left of the drawings.

The device Fig. 2 operates as follows:

When power at low speed is applied to the input shaft I8, the drive will be through the clutch I08 to the ring gear element, to the carrier element, through clutch 58 to the output member. Free wheeling being permitted through either clutch, there will now be no engine braking. This ratio is underdrive, the output shaft rotating at about .7 that of the input.

If it is desired to have the device shift out of underdriv'e into direct drive at about 15 M. P. H., the weight 50 and spring 52 must be so proportioned that at about 10% M. P. H. the weight 50 will move outward and try to enter the opening 98. At about 15 M. P. H. the outward force of the weight will be about double that necessary to move out against the spring resistance.

'ugal force of the weight, in dropping 30% in speed, will be reduced by about half, but since, before deceleration, the weight had double the neo force, then after deceleration and synchronization, it will still have "force enough to enter the opening and will therefore do so.

The drive is now from shaft I8, through clutch I08 to the ring gear element, then through the weight 50 to the output member. The carrier now idles, transmitting no power. Free wheeling being still permitted through the clutch I08, there is no engine braking. This ratio is direct drive, the output and input shafts rotating at the same speed.

If it is desired to have the device shift out of direct drive into overdrive at 35 M. P. H., the weight 88 and spring I0 should be so designed that at about 24 M. P. H., the weight 68 will move outward and try to enter the opening I20. At about 35 M. P. H. the outward force of the weight will be about double that necessary to move out against the spring resistance. This force causes constant rubbing, between 24 /2 and 35 M. P. H., of the outer end of the weight 88 against the inside of the rim H8. The rim is rotating about 30% faster than the weight and therefore the weight may not now enter into the opening I20.

If the engine is again decelerated about 30%, the speed of the weight drops with it that amount, so that the weight 68 and opennig I20 will be synchronized. The centrifugal force of the weight, in dropping 30% in speed, will be reduced by about half, but since, before deceleration, [the weight had double the necessary force, then after deceleration and synchronization, it will still have force enough to enter the opening.

The drive is now from shaft I8 through the weight 88 to the carrier element, to the ring gear element, and through .the weight 50 to the output member. This is"'the overdrive ratio, wherein the input shaft rotates only .7 as fast as the output. Both clutches 54 and I08 are now overrunning, but since the input member is directly connected to the carrier element by the weight 88, and the ring gear element is directly connected to the output member by the weight 50, there is no free wheeling, and consequently there is engine braking as long as overdrive is in effect.

All other things being equal, the structure in Fig. 1 is to be preferred to that in Fig. 2 because, in Fig. 1, the weights are on the members which maintain their speed constant while the openings into which the weights are to enter are deceleraited for synchronization, whereas in Fig. 2 the weights are on the members which must be decelerated, which arrangement results in the long period of rubbing of the weights over their openings under considerable pressure before the weights may be decelerated for synchronization.

Iclaim:

1. Transmission gearing comprising, a reaction gear fixed against rotation, a second gear coaxial therewith, a planet pinion in mesh with both said gears, a planet pinion carrier, an input member, an output member, clutch means for connecting. the carrier to drive the output member forwardly only, a second clutch means for connecting the coaxial gear to the output member, a third clutch means for connecting the coaxial gear to be. driven forwardly only by the input member, and a fourth clutch means for connecting the carrier to the input member.

'2. The structure defined in claim 1 wherein a speed responsive means becomw operative at a predetermined speed to contrd the second clutch means.

3. Thestmcturedefinedinclaimlwhereina I speed responsive means becomes operative at a predetermined speed to control the fourth clutch means.

4. The structure defined in claim 1 wherein one speed responsive means acts at a certain speed to control the second clutch means and a second speed responsive means acts at a difierent speed to control the fourth clutch meam.

5. The structure defined in claim 1 wherein a centrifugal means on the output member becomes operative at a predetermined speed to control the second clutch means.

6. The structure defined in claim 1 wherein a centrifugal means on the carrier becomes operative at a predetermined speed to control the fourth clutch means.

7. The structure defined in claim 1 wherein a centrifugal means on the second gear becomes operative at a predetermined speed to control the second clutch means. I

8. The structure'defined in claim 1 wherein a centrifugal means on the input member becomes operative at a predetermined speed to control the fourth clutch means.

9. An underdrive, direct drive and overdrive gear mechanism comprising, a reaction gear fixed against rotation in either direction, a rotatable gear coaxial therewith, a planet pinion in mesh with both said gears, a planet pinion carrier, means preventing the carrier from rotating faster but not slower than theoutput member, means drivably connecting the input member to the rotatable gear, connecting means normally inoperative but operable to connect the rotatable gear to drive the output member, and a second connecting 'means normally inoperative but operable to connect the input member to drive the carrier. 10. The structure defined in claim 9 with means whereby the first connecting means may be made operative only above a predetermined speed.

11. The structure defined in claim 9 with means whereby the second connecting means may be made operative only above a predetermined speed. 12. The structure defined in claim 9 with speed responsive means whereby the first connecting means may be made operative only after a relatively low speedis exceeded and with a second speed responsive means whereby the second connecting means may be operative only after a higher speed is exceeded.

13. The structure defined in claim 9 wherein the first normally inoperative connecting means comprises a speed responsive means carried on and rotatable with the output member and adapted to move at a predetermined speed to make connection to the rotatable gear.

14. The structure defined in claim 9 wherein the second normally inoperative connecting means comprises a speed responsive means carried on and rotatable with "the carrier element and adapted to move at a predetermined speed to make connection to the input member.

15. The structure defined in claim 9'wherein the first normally inoperative connecting means comprises a speed responsive means carried on and rotatable with the rotatable gear and adapted to move at a predetermined speed to make connection to the output member.

16. The structure defined in claim 9 wherein the second normally inoperative connecting means comprises a speed responsive means carried on and rotatable with the input member and adapted. to move at a predetermined speed to make connection to the carrier.

17. Planetary gearing comprising, a reaction gearfixed against rotation in either direction, a rotatable gear coaxial therewith, a planet pinion in mesh with both said gears, a planet pinion carrier, a means connecting the carrier to drive the output member thru which the output member may overrun the carrier, a means connecting the input member to drive the rotatable gear thru which the rotatable gear may overrun the input member, clutch means engageable to enable the rotatable gear to drive the output member, and a second clutch means engageable to enable the input member to drive the carrier.

18. The structure defined in claim 17 with a speed responsive device for engaging the first said clutch means.

19. The structure defined in claim 17 with a speed'responsive device for engaging the second said clutch means.

20. The structure defined in claim 17 with one speed responsive device operable at a relatively low speed to engage the first said clutch means and a second speed responsive device operable at a' higher speed to engage the second said clutch means.

21. The structure defined in claim 17 wherein the first clutch means comprises a spring restrained centrifugal weight carried on and rotatable in unison with the output member and operable outwardly at or above a predetermined speed to engage a portion of the rotatable gear element.

22. The structure defined in claim 17- wherein the second clutch means comprises a spring restrained centrifugal weight carried on and rotatable in unison with the carrier element and operableoutwardly at or above a predetermined speedto make connection to the input member. 23. The structure defined in claim 17 wherein the-first clutch means comprises a spring restrained centrifugal weight carried on and rotat-.

able in unison with the rotatable gear element and operable outwardly at or above a predetermined speed to engage a part of the output'member.

the second clutch means comprises a spring re-' strained centrifugal weight carried on and rotat able in unison with the input member and operable outwardly at or above a predetermined speed to engage a part of the carrier element.

25. Transmission gearing comprising, a reaction gear fixed against rotation, a second gear coaxial therewith, a planet pinion in mesh with both said gears, a planet pinion carrier, an input member, an output member, means for providing an underdrive ratio between the input and output members comprising a combination of means which connect the coaxial gear to the input member and the carrier to the output member, means for providing a direct drive between the input and output members comprising a combination of means for connecting both the input and output members to the coaxial gear, and means for providing an overdrive ratio between the input and output members comprising a combination of means for connecting the input member to the carrier and the output member to the coaxial gear.

FREDERICK W. CO'I'I'ERMAN.

24. The structure defined in claim 17 wherein 

